Watch our for BA booking hold - they don't let you use Avios

I was searching for flights from CPT to LHR, found a flight, app**** my Avios and could then afford it. Because I was not 100% sure, I paid to have a hold put on the booking (2 pax, R462). After paying for the hold I realised that the fare I had held had gone up by some R3200, and realised that the Avios value had not been deducted from the full fare. I eventually found a human being at BA, who informed me that if you hold a booking, Avios cannot be used. Seriously????? There was noting on the website that I saw to indicate this. So now I will have rebook the flight to use my Avios and forfeit my R462.

Dear BA, as far as I am concerned, this is theft - taking my money but not allowing me the flexibility to pay as I wish without giving me any notification.